youtube-dl/devscripts/youtube_genalgo.py

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2.9 KiB
Python
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2013-06-27 09:15:29 +00:00
#!/usr/bin/env python
# Generate youtube signature algorithm from test cases
import sys
tests = [
("qwertyuioplkjhgfdsazxcvbnm1234567890QWERTYUIOPLKJHGFDSAZXCVBNM!@#$%^&*()_-+={[]}|:;?/>.<",
"J:|}][{=+-_)(*&;%$#@>MNBVCXZASDFGH^KLPOIUYTREWQ0987654321mnbvcxzasdfghrklpoiuytej"),
("qwertyuioplkjhgfdsazxcvbnm1234567890QWERTYUIOPLKJHGFDSAZXCVBNM!@#$^&*()_-+={[]}|:;?/>.<",
"!?;:|}][{=+-_)(*&^$#@/MNBVCXZASqFGHJKLPOIUYTREWQ0987654321mnbvcxzasdfghjklpoiuytr"),
("qwertyuioplkjhgfdsazxcvbnm1234567890QWERTYUIOPLKJHGFDSAZXCVBNM!@#$%^&*()_-+={[|};?/>.<",
"ertyuioplkjhgfdqazxcvbnm1234567890QWERT}UIOPLKJHGFDSAZXCVBNM!@#$%^&*()_-+={[|/;?Y"),
("qwertyuioplkjhgfdsazxcvbnm1234567890QWERTYUIOPLKJHGFDSAZXCVBNM!@#$%^&*()_-+={[};?/>.<",
"{>/?;}[.=+-_)(*&^%$#@!MqBVCXZASDFwHJKLPOIUYTREWQ0987654321mnbvcxzasdfghjklpoiuytr"),
("qwertyuioplkjhgfdsazxcvbnm1234567890QWERTYUIOPLKJHGFDSAZXCVBNM!@#$%^&*()_-+={[};?>.<",
"<.>?;}[{=+-_)(*&^%$#@!MNBVCXZASDFGHJKLPOIUYTREWe098765432rmnbvcxzasdfghjklpoiuyt1"),
("qwertyuioplkjhgfdsazxcvbnm1234567890QWERTYUIOPLKJHGFDSAZXCVBNM!#$%^&*()_+={[};?/>.<",
"D.>/?;}[{=+_)(*&^%$#!MNBVCXeAS<FGHJKLPOIUYTREWZ0987654321mnbvcxzasdfghjklpoiuytrQ"),
("qwertyuioplkjhgfdsazxcvbnm1234567890QWERTYUIOPLKHGFDSAZXCVBNM!@#$%^&*(-+={[};?/>.<",
"Q>/?;}[{=+-(*<^%$#@!MNBVCXZASDFGHKLPOIUY8REWT0q&7654321mnbvcxzasdfghjklpoiuytrew9"),
]
def find_matching(wrong, right):
idxs = [wrong.index(c) for c in right]
return compress(idxs)
return ('s[%d]' % i for i in idxs)
def compress(idxs):
def _genslice(start, end, step):
starts = '' if start == 0 else str(start)
ends = ':%d' % (end+step)
steps = '' if step == 1 else (':%d' % step)
return 's[%s%s%s]' % (starts, ends, steps)
step = None
for i, prev in zip(idxs[1:], idxs[:-1]):
if step is not None:
if i - prev == step:
continue
yield _genslice(start, prev, step)
step = None
continue
if i - prev in [-1, 1]:
step = i - prev
start = prev
continue
else:
yield 's[%d]' % prev
if step is None:
yield 's[%d]' % i
else:
yield _genslice(start, i, step)
def _assert_compress(inp, exp):
res = list(compress(inp))
if res != exp:
print('Got %r, expected %r' % (res, exp))
assert res == exp
_assert_compress([0,2,4,6], ['s[0]', 's[2]', 's[4]', 's[6]'])
_assert_compress([0,1,2,4,6,7], ['s[:3]', 's[4]', 's[6:8]'])
_assert_compress([8,0,1,2,4,7,6,9], ['s[8]', 's[:3]', 's[4]', 's[7:5:-1]', 's[9]'])
def gen(wrong, right, indent):
code = ' + '.join(find_matching(wrong, right))
return 'if len(s) == %d:\n%s return %s\n' % (len(wrong), indent, code)
def genall(tests):
indent = ' ' * 8
return indent + (indent + 'el').join(gen(wrong, right, indent) for wrong,right in tests)
def main():
print(genall(tests))
if __name__ == '__main__':
main()